1. Statement of the Technical Field
This invention relates to power packs which include an electrical system and which have to be flame proof so that they can be used safely in an environment where a spark from the power pack may cause an explosion if it is not flame proof. Such conditions may exist for example in a mine such as a coal mine where methane gas is sometimes present and can be ignited by a spark.
2. Description of the Related Art
Present day power packs used in coal mines frequently comprise an electrically controlled diesel engine and it is necessary to ensure that the electrical system is not capable of igniting methane with a spark.
It is therefore an object of the invention to provide a power pack of this kind which is flame proof so that methane in the environment will not be ignited by a spark therefrom.